android: sposta una vista su touch move (ACTION_MOVE)


177

Vorrei fare un semplice controllo: un contenitore con vista all'interno. Se tocco il contenitore e muovo il dito, voglio spostare la vista per seguire il mio dito.

Che tipo di contenitore (layout) dovrei usare? Come fare questo?

Non ho bisogno di usare una superficie, ma un layout semplice.


Risposte:


235

Qualcosa come questo:

public class MyActivity extends Activity implements View.OnTouchListener {

TextView _view;
ViewGroup _root;
private int _xDelta;
private int _yDelta;

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);

    _root = (ViewGroup)findViewById(R.id.root);

    _view = new TextView(this);
    _view.setText("TextView!!!!!!!!");

    RelativeLayout.LayoutParams layoutParams = new RelativeLayout.LayoutParams(150, 50);
    layoutParams.leftMargin = 50;
    layoutParams.topMargin = 50;
    layoutParams.bottomMargin = -250;
    layoutParams.rightMargin = -250;
    _view.setLayoutParams(layoutParams);

    _view.setOnTouchListener(this);
    _root.addView(_view);
}

public boolean onTouch(View view, MotionEvent event) {
    final int X = (int) event.getRawX();
    final int Y = (int) event.getRawY();
    switch (event.getAction() & MotionEvent.ACTION_MASK) {
        case MotionEvent.ACTION_DOWN:
            RelativeLayout.LayoutParams lParams = (RelativeLayout.LayoutParams) view.getLayoutParams();
            _xDelta = X - lParams.leftMargin;
            _yDelta = Y - lParams.topMargin;
            break;
        case MotionEvent.ACTION_UP:
            break;
        case MotionEvent.ACTION_POINTER_DOWN:
            break;
        case MotionEvent.ACTION_POINTER_UP:
            break;
        case MotionEvent.ACTION_MOVE:
            RelativeLayout.LayoutParams layoutParams = (RelativeLayout.LayoutParams) view.getLayoutParams();
            layoutParams.leftMargin = X - _xDelta;
            layoutParams.topMargin = Y - _yDelta;
            layoutParams.rightMargin = -250;
            layoutParams.bottomMargin = -250;
            view.setLayoutParams(layoutParams);
            break;
    }
    _root.invalidate();
    return true;
}}

In main.xmlsolo RelativeLayoutcon@+id/root


1
@appserv: Nice Job !! Ma mi chiedo perché hai messo layoutPrarms.rightMargin = -250e lo stesso con bottomMargin!! Puoi spiegarlo? Comunque grazie mille !!
Martin pescatore Phuoc,

1
Se la mia memoria mi serve, senza questi valori, la vista verrà compressa quando la si sposta verso destra o verso il basso. Puoi provare a cambiarli e vedere cosa succede.
Vyacheslav Shylkin l'

1
Non devono essere definitivi. Li ho resi definitivi solo per evitare di riassegnare queste variabili.
Vyacheslav Shylkin l'

1
Funziona bene, ma c'è un modo per limitare il movimento dall'esterno dello schermo, il che significa che dovrebbe muoversi solo all'interno del confine dello schermo ..
Daud Arfin,

2
@VyacheslavShilkin L'unico problema che ho riscontrato in questo codice è che non è stato possibile spostare i layout gonfiati dal file xml. È davvero questo il problema del codice o mi sto perdendo a causa della mia ignoranza?
user2498079

356

Ho trovato un approccio semplice per farlo con ViewPropertyAnimator:

float dX, dY;

@Override
public boolean onTouch(View view, MotionEvent event) {

    switch (event.getAction()) {

        case MotionEvent.ACTION_DOWN:

            dX = view.getX() - event.getRawX();
            dY = view.getY() - event.getRawY();
            break;

        case MotionEvent.ACTION_MOVE:

            view.animate()
                    .x(event.getRawX() + dX)
                    .y(event.getRawY() + dY)
                    .setDuration(0)
                    .start();
            break;
        default:
            return false;
    }
    return true;
}

3
@ ruan65 posso limitare la vista per non trascinarmi fuori dallo schermo?
Dhiraj Devkar,

13
Se qualcuno era confuso quanto me sul perché questo funzioni, sappi solo che getX () restituisce una coordinata X relativa alla vista, mentre getRawX () restituisce una coordinata assoluta, relativa allo schermo del dispositivo. stackoverflow.com/a/20636236/4258848
Amer Mograbi il

2
Genius, ho appena aggiunto alcuni controlli dei limiti e funziona benissimo per lo scorrimento orizzontale di un pulsante di scorrimento
Meanman

2
Mentre funziona esattamente come la risposta precedente, è meglio usare i metodi translationX e translationY nel tuo evento move. Per rendere persistente la posizione, impostare le proprietà di layout della vista nell'evento "su". I metodi di traduzione utilizzano il livello hardware del telefono. Proprietà layout no.
Gillis Haasnoot,

3
Possiamo anche usare setXe setYdirettamente, invece di applicare un'animazione di durata 0.
user1032613

11

Seguendo l'approccio @Andrey, se vuoi spostare la vista dal suo centro, devi solo sottrarre la mezza altezza e larghezza della vista al movimento.

float dX, dY;

@Override
public boolean onTouchEvent(View view, MotionEvent event) {
    switch (event.getAction()) {
        case MotionEvent.ACTION_DOWN:
            dX = view.getX() - event.getRawX();
            dY = view.getY() - event.getRawY();
            break;
        case MotionEvent.ACTION_MOVE:
            view.animate()
                .x(event.getRawX() + dX - (view.getWidth() / 2))
                .y(event.getRawY() + dY - (view.getHeight() / 2))
                .setDuration(0)
                .start();
            break;
        default:
            return false;
    }
    return true;
}

3

Stessa implementazione in Kotlin

    rightPanel.setOnTouchListener(View.OnTouchListener { view, event ->
        when (event?.action) {
            MotionEvent.ACTION_DOWN -> {

                rightDX = view!!.x - event.rawX
                // rightDY = view!!.getY() - event.rawY;

            }
            MotionEvent.ACTION_MOVE -> {

                var displacement = event.rawX + rightDX

                view!!.animate()
                        .x(displacement)
                        // .y(event.getRawY() + rightDY)
                        .setDuration(0)
                        .start()
            }
            else -> { // Note the block
                return@OnTouchListener false
            }
        }
        true
 })

La cosa divertente di questa risposta è che l'ho scritta e mi ha aiutato più volte.
Hitesh Sahu,

3

Tocca il contenitore e la vista seguirà il tuo dito.

codice xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
    android:id="@+id/floating_layout"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    >

    <ImageView
      android:id="@+id/btn_chat"
      android:layout_width="42dp"
      android:layout_height="42dp"
      />

<LinearLayout>

Codice Java

public class DashBoardActivity extends Activity implements View.OnClickListener, View.OnTouchListener {

    float dX;
    float dY;
    int lastAction;
    LinearLayout floatingLayout;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_dashboard);

        floatingLayout = findViewById(R.id.floating_layout);
        floatingLayout.setOnTouchListener(this);    



     @Override
    public boolean onTouch(View view, MotionEvent event) {
        switch (event.getActionMasked()) {
            case MotionEvent.ACTION_DOWN:
                dX = view.getX() - event.getRawX();
                dY = view.getY() - event.getRawY();
                lastAction = MotionEvent.ACTION_DOWN;
                break;

            case MotionEvent.ACTION_MOVE:
                view.setY(event.getRawY() + dY);
                view.setX(event.getRawX() + dX);
                lastAction = MotionEvent.ACTION_MOVE;
                break;

            case MotionEvent.ACTION_UP:
                if (lastAction == MotionEvent.ACTION_DOWN)
                    Toast.makeText(DashBoardActivity.this, "Clicked!", Toast.LENGTH_SHORT).show();
                break;

            default:
                return false;
        }
        return true;
    }
}

2

Ti consiglio di usare view.translationX e view.translationY per spostare le tue visualizzazioni.

Snippet di Kotlin:

yourView.translationX = xTouchCoordinate
yourView.translationY = yTouchCoordinate

2

Crea una classe di listener di tocchi personalizzata (in Kotlin):

(Questo codice impedisce alla vista di trascinarsi fuori dalla vista padre)

class CustomTouchListener(
  val screenWidth: Int, 
  val screenHeight: Int
) : View.OnTouchListener {
    private var dX: Float = 0f
    private var dY: Float = 0f

    override fun onTouch(view: View, event: MotionEvent): Boolean {

        val newX: Float
        val newY: Float

        when (event.action) {
            MotionEvent.ACTION_DOWN -> {
                dX = view.x - event.rawX
                dY = view.y - event.rawY
            }
            MotionEvent.ACTION_MOVE -> {

                newX = event.rawX + dX
                newY = event.rawY + dY

                if ((newX <= 0 || newX >= screenWidth - view.width) || (newY <= 0 || newY >= screenHeight - view.height)) {
                    return true
                }

                view.animate()
                    .x(newX)
                    .y(newY)
                    .setDuration(0)
                    .start()
            }
        }
        return true
    }
}

Come usarlo?

parentView.viewTreeObserver.addOnGlobalLayoutListener { view.setOnTouchListener(CustomTouchListener(parentView.width, parentView.height)) }

parentView è il genitore della tua vista.


1

Nel codice seguente, ho creato qualcosa chiamato RegionView( git ), che è un contenitore riutilizzabile responsabile della gestione delle operazioni di trascinamento e zoom per ciascuno dei suoi figli nidificati.

Qui, manipoliamo la tope leftcoefficienti di un bambino View's LayoutParamsal movimento simulare circa il diagramma. Disaccoppiando l'interpretazione della gestione di ciò che è inteso come un'operazione di trascinamento e di ciò che è determinato come un'operazione di scala, possiamo fornire una manipolazione affidabile di un bambino View.

package com.zonal.regionview;

import android.annotation.TargetApi;
import android.content.Context;
import android.os.Build;
import android.os.Vibrator;
import android.support.annotation.Nullable;
import android.util.AttributeSet;
import android.util.Log;
import android.view.GestureDetector;
import android.view.MotionEvent;
import android.view.ScaleGestureDetector;
import android.view.View;
import android.widget.RelativeLayout;

import java.util.HashMap;
import java.util.Map;

/**
 * Created by Alexander Thomas (@Cawfree) on 20/07/2017.
 */

/** Enables users to customize Regions Of Interest on a Canvas. */
public class RegionView extends RelativeLayout implements View.OnTouchListener, GestureDetector.OnGestureListener, ScaleGestureDetector.OnScaleGestureListener {

    /* Member Variables. */
    private final GestureDetector      mGestureDetector;
    private final ScaleGestureDetector mScaleGestureDetector;
    private final Map<Integer, View>   mViewMap;
    private       boolean              mScaling;
    private       float                mScale;
    private       boolean              mWrapContent;
    private       boolean              mDropOnScale;

    public RegionView(Context context) {
        // Implement the Parent.
        super(context);
        // Initialize Member Variables.
        this.mGestureDetector      = new GestureDetector(context, this);
        this.mViewMap              = new HashMap<>();
        this.mScaleGestureDetector = new ScaleGestureDetector(context, this);
        this.mScaling              = false;
        this.mScale                = Float.NaN;
        this.mWrapContent          = false;
        this.mDropOnScale          = false;
        // Register ourself as the OnTouchListener.
        this.setOnTouchListener(this);
    }

    public RegionView(Context context, @Nullable AttributeSet attrs) {
        // Implement the Parent.
        super(context, attrs);
        // Initialize Member Variables.
        this.mGestureDetector      = new GestureDetector(context, this);
        this.mViewMap              = new HashMap<>();
        this.mScaleGestureDetector = new ScaleGestureDetector(context, this);
        this.mScaling              = false;
        this.mWrapContent          = false;
        this.mDropOnScale          = false;
        // Register ourself as the OnTouchListener.
        this.setOnTouchListener(this);
    }

    public RegionView(Context context, @Nullable AttributeSet attrs, int defStyleAttr) {
        // Implement the Parent.
        super(context, attrs, defStyleAttr);
        // Initialize Member Variables.
        this.mGestureDetector      = new GestureDetector(context, this);
        this.mViewMap              = new HashMap<>();
        this.mScaleGestureDetector = new ScaleGestureDetector(context, this);
        this.mScaling              = false;
        this.mWrapContent          = false;
        this.mDropOnScale          = false;
        // Register ourself as the OnTouchListener.
        this.setOnTouchListener(this);
    }

    @TargetApi(Build.VERSION_CODES.LOLLIPOP)
    public RegionView(Context context, @Nullable AttributeSet attrs, int defStyleAttr, int defStyleRes) {
        // Implement the Parent.
        super(context, attrs, defStyleAttr, defStyleRes);
        // Initialize Member Variables.
        this.mGestureDetector      = new GestureDetector(context, this);
        this.mViewMap              = new HashMap<>();
        this.mScaleGestureDetector = new ScaleGestureDetector(context, this);
        this.mScaling              = false;
        this.mWrapContent          = false;
        this.mDropOnScale          = false;
        // Register ourself as the OnTouchListener.
        this.setOnTouchListener(this);
    }

    @Override
    public boolean onTouch(final View v, final MotionEvent event) {
        // Calculate the PointerId.
        final int lPointerId = event.getPointerId(event.getActionIndex());
        // Handle the TouchEvent.
        this.getGestureDetector().onTouchEvent(event);
        this.getScaleGestureDetector().onTouchEvent(event);
        // Did the user release a pointer?
        if(event.getAction() == MotionEvent.ACTION_UP) {
            // Was there a View associated with this Action?
            final View lView = this.getViewMap().get(lPointerId);
            // Does the View exist?
            if(lView != null) {
                // Remove the View from the Map.
                this.getViewMap().remove(lPointerId); /** TODO: Provide a Callback? */
            }
        }
        // Consume all events for now.
        return true;
    }

    @Override
    public boolean onDown(MotionEvent e) {
        // Calculate the PointerId.
        final Integer lPointerId = Integer.valueOf(e.getPointerId(e.getActionIndex()));
        // Fetch the View.
        final View    lView      = this.getViewFor(Math.round(e.getRawX()), Math.round(e.getRawY()));
        // Is it valid?
        if(lView != null) {
            // Watch the View.
            this.getViewMap().put(lPointerId, lView);
            // Configure the Anchor.
            lView.setPivotX(0);
            lView.setPivotY(0);
            // Assert that we handled the event.
            return true;
        }
        // Assert that we ignored the event.
        return false;
    }

    @Override
    public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY) {
        // Are we not scaling?
        if(!this.isScaling()) {
            // Calculate the PointerId.
            final Integer lPointerId = Integer.valueOf(e1.getPointerId(e1.getActionIndex()));
            // Fetch the View.
            final View    lView      = this.getViewMap().get(lPointerId);
            // Is the scroll valid for a given View?
            if(lView != null) {
                // Calculate the Scaled Width and Height of the View.
                final float lWidth    = lView.getWidth()  * lView.getScaleX();
                final float lHeight   = lView.getHeight() * lView.getScaleY();
                // Declare the initial position.
                final int[] lPosition = new int[] { (int)(e2.getX() - ((lWidth)  / 2)), (int)(e2.getY() - ((lHeight) / 2)) };
                // Are we wrapping content?
                if(this.isWrapContent()) {
                    // Wrap the Position.
                    this.onWrapContent(lPosition, lWidth, lHeight);
                }
                // Update the Drag.
                this.onUpdateDrag(lView, lPosition);
            }
            // Assert we handled the scroll.
            return true;
        }
        // Otherwise, don't permit scrolling. Don't consume the MotionEvent.
        return false;
    }

    /** Forces X/Y values to be coerced within the confines of the RegionView. */
    private final void onWrapContent(final int[] pPosition, final float pWidth, final float pHeight) {
        // Limit the parameters. (Top-Left)
        pPosition[0] = Math.max(pPosition[0], 0);
        pPosition[1] = Math.max(pPosition[1],  0);
        // Limit the parameters. (Bottom-Right)
        pPosition[0] = Math.min(pPosition[0], (int)(this.getWidth()  - pWidth));
        pPosition[1] = Math.min(pPosition[1], (int)(this.getHeight() - pHeight));
    }

    /** Updates the Drag Position of a child View within the Layout. Implicitly, we update the LayoutParams of the View. */
    private final void onUpdateDrag(final View pView, final int pLeft, final int pTop) {
        // Allocate some new MarginLayoutParams.
        final MarginLayoutParams lMarginLayoutParams = new MarginLayoutParams(pView.getLayoutParams());
        // Update the Margin.
        lMarginLayoutParams.setMargins(pLeft, pTop, 0, 0);
        // Refactor the MarginLayoutParams into equivalent LayoutParams for the RelativeLayout.
        pView.setLayoutParams(new RelativeLayout.LayoutParams(lMarginLayoutParams));
    }

    @Override
    public boolean onScale(ScaleGestureDetector detector) {
        // Calculate the ScaleFactor.
              float lScaleFactor = detector.getScaleFactor() - 1;
        // Fetch the Scaled View.
        final View  lView        = this.getViewMap().entrySet().iterator().next().getValue();
        // Update the ScaleFactor.
        final float lScale       = this.getScale() + lScaleFactor;
        // Calculate the Proposed Width and Height.
        final int   lWidth  = Math.round(lView.getWidth()  * lScale);
        final int   lHeight = Math.round(lView.getHeight() * lScale);
        // Is the View already too large for wrap content?
        if(lWidth >= this.getWidth() || lHeight >= this.getHeight()) {
            // Don't update the scale.
            return false;
        }
        // Persist this Scale for the View.
        lView.setScaleX(lScale);
        lView.setScaleY(lScale);
        // Assign the Scale.
        this.setScale(lScale);
        // Compute the Position.
        final int[] lPosition = new int[] { Math.round(detector.getFocusX()) - (lWidth / 2), Math.round(detector.getFocusY()) - (lHeight / 2) };
        // Are we wrapping the Position?
        if(this.isWrapContent()) {
            // Wrap the Position.
            this.onWrapContent(lPosition, lWidth, lHeight);
        }
        // Update the Drag.
        this.onUpdateDrag(lView, lPosition);
        // Assert that we handled the scale.
        return true;
    }

    /** Update the Drag. */
    private final void onUpdateDrag(final View pView, final int[] pPosition) {
        // Call the sub-implementation.
        this.onUpdateDrag(pView, pPosition[0], pPosition[1]);
    }

    @Override
    public boolean onScaleBegin(ScaleGestureDetector detector) { 
        // Is the user not dragging at all?
        if(this.getViewMap().size() == 1) {
            // Fetch the View.
            final View lView = this.getViewMap().entrySet().iterator().next().getValue();
            // Initialize the Scale.
            this.setScale(lView.getScaleX()); 
            // Assert that we've started scaling.
            this.setScaling(true);
            // Inform the callback.
            return true;
        }
        // Otherwise, don't allow scaling.
        return false;
    }

    @Override
    public void onScaleEnd(ScaleGestureDetector detector) {
        // Were we scaling?
        if(this.isScaling()) {
            // Assert that we've stopped scaling.
            this.setScaling(false);
            // Reset the Scale.
            this.setScale(Float.NaN);
            // Should we stop dragging now that we've finished scaling?
            if(this.isDropOnScale()) {
                // Clear the ViewMap.
                this.getViewMap().clear();
            }
        }
    }

    /** Returns the View colliding with the given co-ordinates. */
    private final View getViewFor(final int pX, final int pY) {
        // Declare the LocationBuffer.
        final int[] lLocationBuffer = new int[2];
        // Iterate the Views.
        for(int i = 0; i < this.getChildCount(); i++) {
            // Fetch the child View.
            final View lView = this.getChildAt(i);
            // Fetch its absolute position.
            lView.getLocationOnScreen(lLocationBuffer);
            // Determine if the MotionEvent collides with the View.
            if(pX > lLocationBuffer[0] && pY > lLocationBuffer[1] && (pX < lLocationBuffer[0] + (lView.getWidth() * lView.getScaleX())) && (pY < lLocationBuffer[1] + (lView.getHeight() * lView.getScaleY()))) {
                // Return the View.
                return lView;
            }
        }
        // We couldn't find a View.
        return null;
    }

    /* Unused Overrides. */
    @Override public void      onShowPress(MotionEvent e) {  }
    @Override public boolean onSingleTapUp(MotionEvent e) {
        return false;
    }
    @Override public void      onLongPress(MotionEvent e) { }
    @Override public boolean       onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) { return false; }

    /* Getters and Setters. */
    private final GestureDetector getGestureDetector() {
        return this.mGestureDetector;
    }

    private final ScaleGestureDetector getScaleGestureDetector() {
        return this.mScaleGestureDetector;
    }

    private final Map<Integer, View> getViewMap() {
        return this.mViewMap;
    }

    private final void setScaling(final boolean pIsScaling) {
        this.mScaling = pIsScaling;
    }

    private final boolean isScaling() {
        return this.mScaling;
    }

    private final void setScale(final float pScale) {
        this.mScale = pScale;
    }

    private final float getScale() {
        return this.mScale;
    }

    /** Defines whether we coerce the drag and zoom of child Views within the confines of the Layout. */
    public final void setWrapContent(final boolean pIsWrapContent) {
        this.mWrapContent = pIsWrapContent;
    }

    public final boolean isWrapContent() {
        return this.mWrapContent;
    }

    /** Defines whether a drag operation is considered 'finished' once the user finishes scaling a view. */
    public final void setDropOnScale(final boolean pIsDropOnScale) {
        this.mDropOnScale = pIsDropOnScale;
    }

    public final boolean isDropOnScale() {
        return this.mDropOnScale;
    }

}

Qui mostro un caso d'uso di esempio:

package com.zonal.regionview;

import android.support.annotation.Nullable;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.widget.AnalogClock;

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        // Allocate a RegionView.
        final RegionView lRegionView = new RegionView(this);
        // Add some example items to drag.
        lRegionView.addView(new AnalogClock(this));
        lRegionView.addView(new AnalogClock(this));
        lRegionView.addView(new AnalogClock(this));
        // Assert that we only want to drag Views within the confines of the RegionView.
        lRegionView.setWrapContent(true);
        // Assert that after we've finished scaling a View, we want to stop being able to drag it until a new drag is started.
        lRegionView.setDropOnScale(true);
        // Look at the RegionView.
        this.setContentView(lRegionView);
    }

}

0

Modificata un po 'una soluzione fornita da @Vyacheslav Shylkin per rimuovere le dipendenze di tutti i numeri inseriti manualmente.

import android.app.Activity;
import android.os.Bundle;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewTreeObserver;
import android.widget.ImageView;
import android.widget.RelativeLayout;

public class MainActivity extends Activity implements View.OnTouchListener
{
    private int       _xDelta;
    private int       _yDelta;
    private int       _rightMargin;
    private int       _bottomMargin;
    private ImageView _floatingView;

    @Override
    protected void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        this._floatingView = (ImageView) findViewById(R.id.textView);

        this._floatingView.getViewTreeObserver().addOnPreDrawListener(new ViewTreeObserver.OnPreDrawListener()
        {
            @Override
            public boolean onPreDraw()
            {
                if (_floatingView.getViewTreeObserver().isAlive())
                    _floatingView.getViewTreeObserver().removeOnPreDrawListener(this);

                updateLayoutParams(_floatingView);
                return false;
            }
        });

        this._floatingView.setOnTouchListener(this);
    }

    private void updateLayoutParams(View view)
    {
        this._rightMargin = -view.getMeasuredWidth();
        this._bottomMargin = -view.getMeasuredHeight();

        RelativeLayout.LayoutParams layoutParams = new RelativeLayout.LayoutParams(view.getMeasuredWidth(), view.getMeasuredHeight());
        layoutParams.bottomMargin = this._bottomMargin;
        layoutParams.rightMargin = this._rightMargin;

        view.setLayoutParams(layoutParams);
    }

    @Override
    public boolean onTouch(View view, MotionEvent event)
    {
        if (view == this._floatingView)
        {
            final int X = (int) event.getRawX();
            final int Y = (int) event.getRawY();

            switch (event.getAction() & MotionEvent.ACTION_MASK)
            {
                case MotionEvent.ACTION_DOWN:
                    RelativeLayout.LayoutParams lParams = (RelativeLayout.LayoutParams) view.getLayoutParams();
                    this._xDelta = X - lParams.leftMargin;
                    this._yDelta = Y - lParams.topMargin;
                    break;

                case MotionEvent.ACTION_MOVE:
                    RelativeLayout.LayoutParams layoutParams = (RelativeLayout.LayoutParams) view.getLayoutParams();
                    layoutParams.leftMargin = X - this._xDelta;
                    layoutParams.topMargin = Y - this._yDelta;
                    layoutParams.rightMargin = this._rightMargin;
                    layoutParams.bottomMargin = this._bottomMargin;
                    view.setLayoutParams(layoutParams);
                    break;
            }

            return true;
        }
        else
        {
            return false;
        }
    }
}

0

In questo esempio puoi spostare la vista all'interno dei suoi limiti principali indipendentemente dalle dimensioni, dall'animazione impeccabile e dai clic.

Il motivo per cui questa soluzione è superiore ad altri commenti è che questo approccio utilizza un Pad direzionale che si calcola da solo e non trasmette le posizioni di View che sono la fonte di molti bug.

View view;
Animator.AnimatorListener listener;
boolean onMove = false;
boolean firstAnimation = true;
static final int CLICK_DURATION = 175;

float parentWidth;
float parentHeight;

// Those are the max bounds
// within the contianer
float xBoundMax;
float yBoundMax;

// This variables hold the target
// ordinates for the next
// animation in case an animation
// is already in progress.
float targetX;
float targetY;

float downRawX;
float downRawY;

public boolean onTouchEvent(MotionEvent event)
{
    switch (event.getAction())
    {
        case MotionEvent.ACTION_UP:
            if(event.getEventTime() - event.getDownTime() < CLICK_DURATION) click();
            onMove = false;
            break;
        case MotionEvent.ACTION_DOWN:
            firstAnimation = true;
            xBoundMax = parentWidth - view.getWidth();
            yBoundMax = parentHeight - view.getHeight();
            downRawX = event.getRawX();
            downRawY = event.getRawY();
            break;

        case MotionEvent.ACTION_MOVE:
            if(!onMove)
            {
                if(event.getEventTime() - event.getDownTime() < CLICK_DURATION) break;
                else onMove = true;
            }

            // Calculating the position the
            // view should be posed at.
            float offsetX = event.getRawX() - downRawX;
            float offsetY = event.getRawY() - downRawY;
            downRawX = event.getRawX();
            downRawY = event.getRawY();
            targetX = currentX + offsetX;
            targetY = currentY.getY() + offsetY;

            // Checking if view
            // is within parent bounds
            if(targetX > parentWidth - view.getWidth()) targetX = xBoundMax;
            else if (targetX < 0) targetX = 0;
            if(targetY > parentHeight - view.getHeight())targetY = yBoundMax;
            else if (targetY < 0) targetY = 0;

            // This check is becuase the user may just click on the view
            // So if it's a not a click, animate slowly but fastly
            // to the desired position
            if(firstAnimation)
            {
                firstAnimation = false;
                animate(70, getNewAnimationListener());
                break;
            }

            if(listener != null) break;
            animate(0, null);
            break;

            case MotionEvent.ACTION_BUTTON_PRESS:
        default:
            return false;
    }
    return true;
}

// Gets a new animation listener and reset
private android.animation.Animator.AnimatorListener getNewAnimationListener()
{
    listener =  new Animator.AnimatorListener() {
        @Override public void onAnimationStart(Animator animation) { }
        @Override public void onAnimationCancel(Animator animation) { }
        @Override public void onAnimationRepeat(Animator animation) { }
        @Override public void onAnimationEnd(Animator animation) {
            animation.removeListener(listener);
            listener = null;
            view.setAnimation(null);
            animate(0, null);
        }
    };
    return listener;
}

private void animate(int duration, @Nullable Animator.AnimatorListener listener)
{
    view.animate()
            .x(targetX)
            .y(targetY)
            .setDuration(duration)
            .setListener(listener)
            .start();
    currentX = targetX;
    currentY = targetY;
}

private void click()
{
    // Dohere stuff that you desire and than
}

Se il contenitore è all'interno di ScrollView o ScrollView a doppia dimensione, è necessario aggiungere questa riga a onTouch

view.getParent().requestDisallowInterceptTouchEvent(true);

0

Lo stesso della risposta di @ Alex Karshin , cambio un po '.

public class MovingObject implements OnTouchListener {
private RelativeLayout.LayoutParams lParams;
private PointF viewPoint, prePoint, currPoint;

public MovingObject() {
    lParams = null;
    viewPoint = new PointF();
    prePoint = new PointF();
    currPoint = new PointF();
}

public boolean onTouch(View view, MotionEvent event) {
    switch (event.getAction() & MotionEvent.ACTION_MASK) {
    case MotionEvent.ACTION_DOWN:
        viewPoint.set(view.getX(), view.getY());
        prePoint.set(event.getRawX(), event.getRawY());
        lParams = (RelativeLayout.LayoutParams) view.getLayoutParams();
        break;
    case MotionEvent.ACTION_UP:
        break;
    case MotionEvent.ACTION_POINTER_DOWN:
        break;
    case MotionEvent.ACTION_POINTER_UP:
        break;
    case MotionEvent.ACTION_MOVE:
        currPoint.set(event.getRawX(), event.getRawY());
        moveToCurrentPoint(view);
        break;
    }
    view.invalidate();
    return true;
}

private void moveToCurrentPoint(View view) {
    float dx = currPoint.x - prePoint.x - prePoint.x + viewPoint.x;
    float dy = currPoint.y - prePoint.y - prePoint.y + viewPoint.y;
    lParams.leftMargin = (int) (prePoint.x + dx);
    lParams.topMargin = (int) (prePoint.y + dy);
    view.setLayoutParams(lParams);
}
}
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